In a first category of prior art automatic driver systems, in particular for rail vehicles, the systems are linear type servo-control systems.
Such prior art automatic driver systems take account of certain external parameters and constraints such as: track profile, i.e. peaks and slopes; the possibility of allowing the vehicle to coast; passenger comfort, i.e. avoiding sudden changes between traction and braking; protecting other vehicles; and obeying the speed limit in each section.
However, such prior art automatic driver systems do not take account of certain other external parameters and constraints such as: the energy consumed by the vehicle; and guaranteed travel time.
In the state of the art, automatic driving in the Metro is performed in such a manner as to provide standard working. Standard working corresponds to a plurality of determined speed profiles between stations. A particular profile is selected by the network control system from a fixed number of options while the train is standing in a station. Each speed profile corresponds to a given travel time, but traffic disturbances can give rise to significant lateness. That method of generating a speed reference cannot catch up such lateness. In addition, energy consumption is optimized by coasting at predefined positions along the track.
The article "Design, realization, and improvement of an optimum fuzzy controller for a running train", by N. Geng and I. Muta, published in the Japanese Journal of Fuzzy Theory and Systems, Vol. 5, No. 1, 1993, pages 133 to 146, and the article "Total system for rapid transit and trends in control electronics for railway vehicles", by A. Oazama and M. Nomi, published in Hitachi Review, Vol. 35 (1986), No. 6, pages 297 to 304, illustrate prior art systems for automatic train driving.